The objective of this proposal is to develop, cooperatively, new or improved assessment methodologies and instruments for evaluating clinical improvement in AD clinical trials. The two central questions in evaluating treatment efficacy are whether the drug has a therapeutic effect, and if so, whether the effect observed is clinically meaningful and of sufficient magnitude to outweigh possible risks. Obtaining accurate answers hinges on using well-designed protocols which employ appropriate, sensitive, reliable and clinically relevant outcome measures. Reasonably adequate measures are currently available for the four primary AD assessment categories: Measures of cognitive function (comprehensive scales and psychometric batteries), global scales, activities of daily living (ADL) scales, and non-cognitive behavioral symptom scales. However, current measures in each of these domains have significant limitations. Two additional assessment domains are of growing importance for widening patient access to clinical trials: measures for severly impaired patients, and non-English scales. Relatively little previous work has been done in these two areas. The general goal of this proposal is to capitalize on the unique expertise, experience, patient resources and staff of the Alzheimer's Disease Study Units (ADSUs) to develop improved or new outcome measures in each of these six assessment domains. To achieve this goal, we propose (1) to form subcommittees of experts for each assessment domain which will conceptualize, develop, and plan the evaluation of new measures in each domain. A Consortium Assessment Committee, consisting of a chair and the chairs of each assessment subcommittee, will plan and coordinate the overall program to develop new measures; (2) to utilize the staff and patient populations of the 30 participating ADSUs to assess the utility, reliability and validity of the new scales and tests that are developed, and (3) to field-test the utility and drug sensitivity of the new measures developed by including them as secondary outcome measures in multicenter clinical trials conducted by the ADSUs.